Correct method to test diaghragm first stage after completing annual service

[ParrotfishNick]

Hello to all the professiona technicians out there. I am looking for as many responses to the following question from experienced scuba equipment technicians. What is the correct way to test a first stage scuba regulator once an annual service is completed?

I have two basic technician courses for Mares and Cressi gear. I by no means think that I am an expert and this is why I am wanting to lean on those industry professionals willing to help a newbie so to speak. I would greatly appreciate as much detail on the process of the testing following the service and the reasons for this process. I recently had a conversation with a dive professional who is also a tech for whom I am working that made me question some of the things I had learned (or not learned) during my past training. In all honesty, I have felt that the training I have received was either not long enough, not in depth enough or lacking real world practical experience with regs needing servicing. I have found from the work I have done, that I have learned much more from working on actual regulators than I did during my training.

Because regulators are basically life support systems underwater, I take working on them very seriously and want to be the best technician I can be, understand the processes and not just following a set of steps. I greatly appreciate your time and your help

 

[Griffo]

SCUBA REGULATOR MAINTENANCE AND REPAIR by Vance Harlow

Is what most people point people at. There's another one too but it's escaping my mind for the moment.

 

[happy-diver]

Regulator Savvy Book | Scuba Tools

 

[ams511]

What is the correct way to test a first stage scuba regulator once an annual service is completed?

Wouldn't this depend on the manufacturer and the equipment you have at the shop?

 

[GJC]

Hello to all the professiona technicians out there. I am looking for as many responses to the following question from experienced scuba equipment technicians. What is the correct way to test a first stage scuba regulator once an annual service is completed?

I have two basic technician courses for Mares and Cressi gear. I by no means think that I am an expert and this is why I am wanting to lean on those industry professionals willing to help a newbie so to speak. I would greatly appreciate as much detail on the process of the testing following the service and the reasons for this process. I recently had a conversation with a dive professional who is also a tech for whom I am working that made me question some of the things I had learned (or not learned) during my past training. In all honesty, I have felt that the training I have received was either not long enough, not in depth enough or lacking real world practical experience with regs needing servicing. I have found from the work I have done, that I have learned much more from working on actual regulators than I did during my training.

Because regulators are basically life support systems underwater, I take working on them very seriously and want to be the best technician I can be, understand the processes and not just following a set of steps. I greatly appreciate your time and your help

Can you describe what was included in your basic technician courses for Mares and Cressi and how long those courses were?

 

[Caveeagle]

Your question asks about “testing”, but I suspect you want to know about set up and tuning the intermediate pressure. Am I right?

 

[tbone1004]

one useful trick with diaphragm regs. When you are done assembling them, get the cap with the spring on but don't put any spring pressure on the diaphragm. Pressurizing the reg with an IP gauge and let it sit for 10 minutes with no spring pressure. Since there is no spring pressure, there shouldn't be any gas that gets by the seat. If there isn't any IP inside of the system after 10mins, then you are not getting any leakage past the seat and are unlikely to experience any IP creep. It's in the Poseidon manuals, but I haven't seen them anywhere else

 

[halocline]

What is the correct way to test a first stage scuba regulator once an annual service is completed?

This is kind of an odd question, because there are probably a variety of answers depending on which manufacturer you're talking about. But.....in terms of testing your reg post service, (as opposed to checking your work as you go along, i.e. torque values, inspecting parts, etc...) basically you want to make sure there are no leaks and that IP is correct and stable. I'm sure you understand that, correct? There are different ways of checking for those things, maybe you could ask more specific questions. Personally, I check for leaks by pressurizing (with a 2nd stage attached) and submerging, looking for any bubbles. I also put an IP gauge on an inflator hose and cycle the reg several times, then leave it pressurized for an hour or two, to make sure there is no creep at all.

I don't know about most manufacturers, but SP says to check IP at 300 and 3000 PSI. I do that by pressurizing, shutting off the tank valve quickly, and bumping the purge until the SPG reads 300. Then I open the valve again and let it fully pressurize to check at 3000.

 

[JackD342]

Typo? Perhaps meant "if there isn't any"?

If there is any IP inside of the system after 10mins, then you are not getting any leakage past the seat and are unlikely to experience any IP creep.

 

[tbone1004]

@JackD342 correct, sorry. Staying at @The Chairman 's house and was typing that while waiting on his leg to catch up so we could go dive and didn't proof read.

@halocline the dual pressure is to make sure the balance ports are working properly. With unbalanced regs it is critical to tune at one of the IP extremes since it will shift. With Poseidon Jetstream/Xstreams it is critical that you actually have the first stage at like 4000psi because the IP is lowest when the tank pressure is highest. If you tune the reg at 3000 then put it on a cave filled tank at 3600-3800psi the second stage won't have enough IP to seat properly and will leak a little bit. Once the IP is as low as it will go, you tune the reg and then the cracking pressure will increase as tank pressure goes down and IP goes up a few psi *very little, but when you are tuning to the bitter end of where the regs are stable it is important*. With the Cyklon, being a normal downstream unbalanced second stage, you have to tune it at like 200-300psi where the IP is highest otherwise it will start freeflowing when the tank pressure drops and this one gets gradually easier to breathe as the tank pressure drops. It is essentially negligible with balanced second stages, but with any unbalanced second stage it is super important to do the dual pressure checks because no balanced first stage is ever perfectly balanced. Since I have almost all Poseidon's I actually do that dual PSI check with a regulator similar to the ones used on fill stations in order to get that big of a pressure differential. I have a valve that had the dip stick port tapped with 1/4" NPT and the same Swagelok QF4 quick disconnect that I have on my fill whips/adapters so I can hook it up directly that way. If I am not on a fill station, I can connect to a DIN port from the fill whip and test off of a tank but the high pressure is limited by whatever is in that tank